Frost research targets yield losses
Frost causes yield losses in the southern grain-growing region that are said to cost the Australian grains industry about $360 million a year.
The scale of these losses has prompted the GRDC to invest about $13.5 million in frost-focused research projects since 1999.
This commitment to frost research is continuing with two new GRDC-funded studies starting in 2013. Both studies are expected to inform future frost research and management decisions, and improve knowledge of frost-tolerant varieties to reduce yield losses.
One project that runs until 2015 will examine the severity, timing and frequency of frosts in different agroecological zones, drawing on historical data and simulation modelling.
The other new project will look at yield potential in frost-tolerant wheat and barley varieties. The results of this three-year project will be made available through crop variety guides and the GRDC’s National Variety Trials (NVT) program.
GRDC Southern Panel Chair David Shannon emphasises the difficulty in researching frost as a major production constraint facing growers.
“Frost can be unpredictable and its impact can vary depending on the conditions and the stage of crop growth,” Mr Shannon says.
Research shows that the number of frosts has increased across the country and more frost events are occurring later in the year, he says.
“This was evident in many parts of the southern cropping region last year, particularly in southern New South Wales, South Australia and Victoria. Frosts in September to October caused up to 80 per cent yield losses in individual crops,” he says.
However, Mr Shannon says measures to reduce the risk of frost damage, such as delaying sowing, could result in large yield penalties.
He says issues with frost damage highlight the importance of genetic research into the issue.
The GRDC, the University of Adelaide and the Department of Agriculture and Food, Western Australia, established the Australian National Frost Program in 2012 to provide a national frost screening facility. Scientists are developing frost sensitivity ratings for current wheat and barley varieties at this new facility.
National pre-breeding research is also seeking to identify and select frost-tolerant wheat and barley germplasm for use in breeding programs to reduce frost sensitivity in commercial varieties.
University of Adelaide researcher Dr Timothy March says one study showed that all the varieties tested were susceptible to severe frost conditions, which are below minus 4ºC in wheat and minus 6ºC in barley.
“However, genetic variation has been identified that induces grain sterility under mild frost conditions,” Dr March says.
“What is not yet well established is if frost-induced sterility is directly related to yield loss, and if certain varieties are better able to compensate through other mechanisms, such as increasing grain size or better grain-filling on secondary tillers.”
0419 830 700
Dr Timothy March
08 8313 6700
A GRDC Managing Frost Risk booklet can be download via www.grdc.com.au/GRDC-Booklet-ManagingFrostRisk or a hard copy is available for $10 plus postage and handling from Ground Cover Direct, free phone 1800 110 044 or email email@example.com
GRDC Project Code DAW00162, CSP00143, UA00114, UA00063, UA00100
Region South, National, North, West